1996 SL2 having a rough idle and running rich. PLease advise. Problem happens only at idle. throwing code p0172 rich bank 1 and p1336 misfire. have already replace temp sensor, full tuneup, iac and pcm. I love this car, but am about to drive it over a brigde!!!Please, anyone with any ideas..............

Being a 96' I am guessing you have some miles on the car... And what you're describing sounds like an ignition related problem.


Have you replaced plugs? Are they gapped correctly? If so, have you checked your plug wires? If you've done all this I would check the coil packs.

actually, car has 64,000 miles. and yes plugs have been replaced and gapped by saturn dealer....2 times.......advise

I think I would still narrow out the coil packs.


Otherwise perhaps dirty air cleaner, plugged catalytic converter, bad oxygen sensor.... Could be a number of things.

coil packs are good....am leaning towards cat, but no smell, engine code or anything for it. I am actually a service writer at a honda dealer and have had this car on the lifts several times and do not see any visible problems. ever see anything electrical causing issue?

Other than the ignition. No I haven't. The only other electrical related would be the Computer, which I know nothing about. Don't like computers, so I stay away from them as much as possible. Carburetors Are King!

well, thank you...im going to do a bit more diag and see what i find.....will post when problem solved for future reference!!

P0172 = Fuel Trim System Rich Bank 1

However, I believe
P1336 = Crankshaft Position (CKP) System Variation Not Learned
(not a misfire code)

Sounds like a bad Crank Position Sensor to me....

Not sure about the running rich part, but this may be default behavior the PCM can't figure out where the crank is in its rotation...

If the fuel rich code remains, I would (as already suggested) check out the 02 sensor (s) -- particularly the front one.

Derf

i have had the bank 1 code before, you need new fuel injectors, trust me

With the engine running, pull the vacuum reference line off the pressure regulator and see if it is leaking fuel out the regulator.


My 95 SL2 is doing the same thing.